The present invention generally relates to an audio video system having audio video devices such as televisions, VTR, and audio equipment connected at a plurality of stations to a common information transmission path, and more particularly, to a picture display method for displaying the functional displays of the respective stations on a monitor display screen to allow users to input operational commands in accordance with the monitor displays.
Conventionally, when the functional displays of all the stations connected in the system, and the displays of a menu are effected, the central computer retains all the functional displays and the picture data of all the stations to effect integrated control and processing of the displays as demanded by a user.
However, such conventional techniques have the following problems.
(1) Since the central computer controls the picture display data of all the stations connected to the system, the data amount to be controlled is enormous.
(2) Since the central computer controls the picture display data of all the stations connected to the system, it is difficult to cope with the picture displays of a new station when the new station is connected to the system, or even when the types or displays are replaced by new ones in a existing station.
As a method of solving the above described problems, the technique of Japanese domestic patent publication No. 2-146558 has been proposed.
This patent technique is characterized in that in a communication system in which a controller composed of a control portion, a display portion, an input portion and a communication control portion is connected via a common communication path to a plurality of terminals provided with a communication portion. A means is adapted to control the corresponding terminal by the selection of the control item and the control content displayed on the display portion of the controller so as to control the terminals from the controller. A plurality of types of basic picture displays to be displayed on the display portion are built in within the controller. A plurality of terminals connected with the common communication path respectively retain the picture information necessary for their own control. The picture information which is an object with respect to the data reception from the controller is transmitted to the controller so as to display on the display portion the picture necessary for the control effected on the side of the controller.
However, in the method of the above described patent, the following problems remain unsettled.
(1) The controller is required to previously contain the basic pictures of the terminals thus requiring that the terminals which may be connected with the audio video system be known in advance.
(2) Although the respective terminals contain the data to be displayed, the controller always has a control right of the picture display as to which terminal picture is displayed in which order, so that a terminal cannot on its own display a desired display in accordance with a demand of the user.